On the basis of the existing originally modified calculation models of theoretical combustion temperature(TCT),some factors,such as the combustion ratio of pulverized coal injection(PCI),the decomposition heat of PCI and the heat consumption of SiO2 in ash reduced in high temperature environment,were amended and improved to put forward a more comprehensive model for calculating TCT.The influences of each improvement on TCT were studied and the results were analyzed compared with those of traditional model and originally modified model,which showed that the present model could reflect the thermal state of a hearth more effectively.
WU Sheng-li LIU Cheng-song FU Chang-liang XU Jian KOU Ming-yin
The mathematical model of minimum safety factor that investigated the collapse trends of coke layer under different charging parameters was established firstly on the basis of the slope stabilization theory in soil mechanics,and then the model of burden profile after coke collapse was improved by adopting the predetermination of quadratic curve and energy correction methods.The research will provide theoretical evidences for describing the coke profile more accurately and technical direction for choosing suitable charging parameters of blast furnace.The results show that:it is helpful to improve the stability of coke layer with increasing chute inclining angle and length of the coke flat;when the main falling point of ore moves toward furnace wall or the coke flat is wider,the curve radian of burden profile after coke collapse becomes smaller;the ore to coke ratio distribution agrees with the gas top temperature measurement well under considering coke collapse comparing with the result of ignoring coke collapse.
WU Sheng-li FU Chang-liang LIU Cheng-song XU Jian KOU Ming-yin
